US1929989A

US1929989A - Coping saw

Info

Publication number: US1929989A
Application number: US639661A
Authority: US
Inventors: Dwight E Priest
Original assignee: PARKER WIRE GOODS Co
Current assignee: PARKER WIRE GOODS Co
Priority date: 1932-10-26
Filing date: 1932-10-26
Publication date: 1933-10-10
Anticipated expiration: 1950-10-10

Description

Oct 10, 1933. -r v 1,929,989

, COPING SAW Filed Oct. 26, 1932 201/95? .2: PI-asl" Max-W0" Patented Oct. 10, 1933 Parker Wire Goods Company,

Worcester,

' Mass, a corporation ofMassachusetts Application October 26. 1932." Serial No.639,661

Claims. (Cl. 145-33)" This invention relates to a coping or jig saw of the type in which a light thin saw blade is removably mounted in asuppor-ting and tensioning frame. j

5 It is the general object of my inventionto improve the construction of such saws to the end that they may be economical in manufacture, reliable in operation and satisfactory in use.

To the accomplishment of this general object,

important features of my invention relate to the provision of an improved frame member for the saw, and to the provision of. improved devices for securing and tensioning a saw blade therein.

My invention further relates to arrangements 5 p and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claims.

A preferred form of the invention is shown in the drawing, in which Fig. l is a side elevation of my improved saw Fig. 2 is a side elevation showing a preliminary step in the manufacture of the frame member;

Fig. 3 is an end view of the frame member, looking in the direction of the arrow 3 in Fig. 2;

member, looking in the direction of the arrow 4 in Fig. 1;

Fig. 5 is an enlarged detail elevation, looking in the direction of the arrow 5 in Fig. 2;

Fig. 6 is an enlarged view of the saw securing member, looking in the direction of the arrow 6 in Fig. 1;

Fig. 7 is an enlarged view, taken along the line '77 in Fig. 1;

Fig'. 8 is a plan view of a saw blade;

Fig. 9 is a side View of the tensioning member at a preliminary stage;

Fig. 10 is an end view, looking in the direction of the arrow 10 in Fig. 9;

Figs. 11 and 12 are side elevations showing further successive steps in the production of the tensioning member;

Fig. 13 is an end View, looking in the direction of the arrow 13 in Fig. 12;

Fig. 14 is a plan view of the completed tensioning member, and

Fig. 15 is a detail sectional side elevation show--, ing the construction of the saw handle.

Referring to the drawing, I have shown a 5 0 coping or jig saw comprising a framemember 20, a saw S, asecuring member 21, a tensioning member 22 and a handle H. The frame member is preferably formed from a single piece of wire rod 24 of circular cross section, which is first 55 bent to a general U-shape as indicated in Fig. 2.

Fig. 4 is an end view of the finished frame The ends of the wire rod 24 are bent to the circular shape indicated at 25 in Fig. 3 and provide eyes or bearingsfor the securing member21 and tensiom'ng member-22. Notches 26 (Figs. 2 and 5) and 27: (Figs. 2 and 7) are provided for a purpose to1be described in the left-hand face of each curved end or hearing portion 25 as viewed Fig. 1. l

The frame'memberthus constructed is then subjected to a pressor hammer operation by which the round rod 24 is flattened, to the shapeindicated inthe frame 20 in Figs. 1 and4. The subjection of the frame to this pressing or flattening operation after being. bent tothe; U-shape form shown in Fig. 2 substantially increases the stiffness of the frame over that of the round rod from which it is constructed.

The securing member 21 (Figs. 6 and 7) is preferably formed from a single piece of half round rod bent to provide a head or end portion 30 and a body portion 31. The two parts of the body portion 31 are spaced apart to provide a slot 33 adapted to receive an end portion of the saw S. The parts 31 are also provided with angularly disposed transverse slots 35 (Figs. 1 and 6) adapted to receive a cross pin 36 in one end of the saw S. The slots 35 may be formed in any convenient manner, as by a milling or punching operation.

The inner face of the head portion 30 is engaged in certain of the notches 27 when the parts are assembled and is thus held firmly from accidental angular displacement.

The tensioning member 22 is also preferably formed from a single piece of half roundrod, which is first bent to the narrow U-shape indicated at in Figs. 9 and 10. A cross pin 41 is then placed between the spaced portions of the securing member 40, as indicated in Fig. 11,- and the assembled

parts

40 and 41 are subjected to a press operation by which the cross pin 41 is firmly gripped between the two side portions of the tensioning device and by which also a slot 42 is provided to receive an end portion of the saw S.

The portion of the U-shaped member at the opposite side of the cross pin 41 is pressed to subin certain of the notches 26 in the frame member 20, as indicated in Fig. 15.

The handle H has a nut 50 firmly seated in a recess 51, and by turning the handle the tensioning device 22 is drawn through the eye or bearing each direction the saw will be firmly held. from angular displacement.

Having thus described my improved; coping g saw, it will be evident that: tlamseveral partsaof the saw may each be very rapidly and economi'' cally manufactured, and that. each part'is par-.

ticularly well adapted to its intended purpose.

Having thus described my invention and the. advantages thereof, I do not wish to be limited to the details disclosed, Otherwise than as setforth in the claims, but what-I claim is-:'--

I. In a coping saw, an integral one-piece frame member having end portions of round wire rod bent into loops to-form bearings, and having. a U

shaped connecting portion which is substantially thinner and wider than said circular wire rod and which has flat side surfaces disposed parallel.

to the plane of said frame member, whereby said frame member is substantially stiflened withoutincrease in n'iaterial'.

2. In a eoping saw, a securing device formed froma single piece of ball roundstock bent upon itself to provide a transversely extended head.

and parallel legs spaced apart to provide a longitudinal slot for one end of a saw blade, said parallel legs being transversely slotted to receive a cross pin in said saw blade.

3. In a copingsaw; a tensioning device formed from a single piece of half round stock and a cross pin said .stockbeing bent upon itself to provide parallel leg portions and said leg portions being compressed about said cross pin and being spaced apart at one side of said pin and atthe open end of said device to provide a longitudinal slot for one. end of a saw blade. 4. In a coping saw, a tensioning device formed from a. single piece of half round stock and a cross pin, said stock being bent uponitself to provide parallel leg portions and said leg portions being compressed about said cross pin and being spaced apart at one side of said pin and at the open end of said device to provide a longitudinal slot for one end of a saw blade, and said spaced-apart leg portions being transversely slotted to receive a cross pin in said saw blade. r

5. In a copingsaw, a tensioning device formed from a single'piece of half round stock and'a cross pin, said-stock being bent upon itself to provide 'parallei legportions and said leg portions being compressed about said cross pin and being spaced apart atone side of said pin-and at the open-end of said device to provide a longitudinal slot-for one end of a saw blade, said tensioningdevice being also screw-threaded at the opposite side of'saicl cross pin and at the closed end of said device.

- DWIGHT E. PRIEST.